Stability of commercial formulation

Adhya TK, Barik S, Sethunathan N. 1981. Stability of commercial formulation of fenitrothion, methyl parathion, and parathion in anaerobic soils. J Agric Food Chem 29 90-93. 

Comparative studies may also be useful in evaluating the relative stability of commercial formulations of the same drug from different suppliers. In these cases, the cause(s) of differences in stability may be difficult to determine since different sources of active ingredient and different excipients may all be variables that affect stability. 

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